1. FIELD OF THE INVENTION
The present invention relates to a writing and/or reading apparatus of the type in which a writing head and/or reading head is displaced to a desired track position of a plurality of tracks defined on the surfaces of a disc-shaped recording medium and the desired data is written to and/or read out of the surfaces of the recording medium.
2. DESCRIPTION OF THE PRIOR ART
Conventionally, as in the data writing and/or reading apparatuses of the type described above, a floppy disc drive (to be referred to "FDD" in this specification hereinafter) is used as external storage for a computer. The desired data is written to and/or read out of the surfaces of a so-called flexible floppy disc.
In the case of FDD of the type described above, a head carriage upon which are mounted the one or more heads is supported that it can move freely in the direction in which a plurality of recording tracks are defined on one or both of the surfaces of the recording medium. Therefore, the heads can be moved to the desired recording tracks so that the desired data can be written and/or read out. And there have been proposed various guide means for guiding head carriages.
However, in the case of the apparatus (such as an FDD) of the type in which heads are made in contact the surfaces of the recording medium (such as a floppy disc) which is turning, thereby writing and/or reading the data, because of frictional force produced by frictional contact between the head or heads and the surface of the recording medium, the following problems arise.
Firstly, at the point of contact with the disc, the head is forced in a direction perpendicular to the radial direction in which the head is displaced so that the head and the head carriage carrying the head are forced in the direction of disc rotation resulting in tracking error. Secondly, conditions of the engagement between the head carriage and guide means are adversely affected so that the head carriage is forced to vibrate or oscillate, also resulting in tracking error. Consequently, a high-quality writing and/or reading operation cannot be carried out.